Like the entity of its title, “Waves” moves in crests and crashes, mostly that of the fates and emotions of its characters, and the profound and lingering impact of those actions. Wunderkind filmmaker Trey Edward Shults (“Krisha,” “It Comes at Night”) immerses us in the ebbs and flows of life of an African American family in South Florida in a way that feels like cinéma-vérité, but the beginning and end – a girl riding a bike along a serene esplanade – bookends the film with poetry and purpose.

Following that scene of tranquil innocence, we jump into a car full of teens joyriding across a bridged expanse, the sky above and water below both impeccably blue as music blares on the radio. The camera, seemingly hung disco ball style from the roof of the SUV, swirls around and around as we catch glimpses of happy faces singing along and legs, arms and heads lolling out the window. It’s a scene of pure, energetic joy, but glorious and uplifting as it is, there’s an imminent undercurrent of fragility and peril.

Two of the teens, Tyler (Kelvin Harrison Jr.) and Alexis (Alexa Demie, from the TV series “Euphoria”) make a tumultuous pair. When it’s good, it’s great, but ripples in the relationship lead to bigger ramifications. Tyler’s a rock star of a wrestler with a shot at a college scholarship, something his controlling father, Ronald (Sterling K. Brown), drills into him on a daily basis, making him do extra weight training after practice and breaking down his technique ad infinitum – after one or two of these life coaching lecturers, you too will want to slip away to your room. The first setback for Tyler comes in a potentially career-ending shoulder injury that leads to the use of alcohol and drugs to cope. Then Alexis mentions the words: “I’m late.”

How that conundrum is wrestled with (and it takes wildly unexpected turns) arrives early in the film; then there’s a dramatic focal shift to Tyler’s kid sister, Emily (Taylor Russell), who struggles in the aftermath but ultimately finds comfort and romance in the company of Luke (Lucas Hedges), another wrestler and something of a goofball romantic despite having his own issues (mom died when he was young, and he’s estranged from his father).  For all the natural and architectural beauty Shults finds in South Florida – the setting for other notable recent indie greats as “Moonlight” (2016) and “The Florida Project” (2017) – it is not the happy place it appears to be on the outside.

Like “Moonlight” – and comparisons between the films are inevitable, though they are very different – the matter of race in “Waves” is not embossed or underscored. But it’s there, subtly and provocatively. About the most overt the film gets is when Ronald, who along with his wife (Tony winner Renée Elise Goldsberry, “Hamilton”) has provided the children a spacious and nurturing environment, tells Tyler solemnly, “ We are not afforded the luxury of being average. Got to work 10 times are hard just to get anywhere.” It lingers.

Of “Waves,” not enough can be said about the cast. Brown’s prideful patriarch commands the screen so throughly that I can’t imagine he’s not in the Best Supporting Actor conversation come year end; but the whole tsunami of emotions doesn’t crest or swell without Harrison Jr., seen this year in “Luce.” His once hopeful character goes through a gantlet of external and self-imposed torment – a bravura performance from such a young actor who has to hit such a wide range of emotions, so high and so low, and something he takes to the mat each time, giving Shults’ middle American saga its brine and soul.